1. Technical Field
The present disclosure generally relates to backlight modules, and particularly to a backlight module with satisfied light uniformity.
2. Description of the Related Art
A typical LCD device includes a liquid crystal display panel, and a backlight module mounted behind the liquid crystal display panel. The backlight module mainly comprises a light source and a light guiding plate. The light guiding plate is generally made of a transparent acrylic plastic, and is used for guiding the light beams emitted by the light source in order to uniformly illuminate the liquid crystal display panel.
Nowadays, the light source of the backlight module includes red LEDs, green LEDs, and blue LEDs arranged on a substrate. White light is obtained by mixing light emitted by the red, green, and blue LEDs. However, the LEDs arranged on lateral sides of the substrate couldn't thoroughly mix. Light output from a light output surface of the light guiding plate may be non-uniform. In order to mix the light emitted by the light beams uniformly from the light output surface, a wavelength-selective reflectors is provided at a front of the light source to reflective light with the same colors; therefore, it can improve the mixing degree of the light via enhancing the distance that the light travels. Alternatively, reflectors are provided at lateral sides of the light guiding plate to reflect light emitted by the outmost light source to center area, and mix with light emitted by the center light source to obtain white light. Therefore, it can improve the light uniformity. However, because the light reflected by the reflectors for many times, the luminous intensity of the beams may be lessened to an unacceptable level.
Therefore, what is needed is a backlight module to overcome the above described shortcomings.